1. Field of the Invention
The present invention relates to a door locking handle assembly of a pull-out and side-swinging lever-action type. The door locking handle assembly is used in a plugboard box and the like containing various instruments therein, for locking, unlocking, opening and closing its door.
2. Description of the Prior Art
Already disclosed in Japanese Patent No. 2504714 is a conventional door locking handle assembly of a pull-out and side-swinging lever-action type. This conventional door locking handle assembly comprises: a stationary casing fixedly mounted on a door, the stationary casing being provided with a recess in its front surface and a cylindrical portion in its base-end portion, wherein the cylindrical portion projects rearward from a rear surface of the base-end portion; a main pin rotatably mounted in the cylindrical portion of the base-end portion of the stationary casing in an insertion manner, the main pin being non-axially slidable in the cylindrical portion and having its rear-end portion fixed to a catch plate, wherein the catch plate is engaged with and disengaged from a receiving portion of a stationary frame element, and the main pin is provided with a connecting boss portion in its front-end portion; and a control handle which has its base-end portion pivoted to the connecting boss portion of the main pin through a cross pivot so that the control handle is foldable into and projectable from the recess in the stationary casing, whereby the control handle is side-swingable in its projected position.
In this conventional door locking handle assembly, in order to hold the control handle in each of: its retracted position in which the control handle is fully received or embedded in the recess of the stationary casing; its projected or pulled-out position in which the control handle is pulled out of the recess in the stationary casing; and its side-swung or -turned position in which the control handle is turned toward its unlocked position, there is further provided a compression coil spring for urging a spring shoe plate forward, wherein: the compression coil spring is received in a hollow portion provided behind the spring shoe plate which is provided with a central through-hole; the connecting boss portion of the main pin is inserted into the central through-hole of the spring shoe plate so that the spring shoe plate is non-rotatably mounted on the connecting boss portion of the main pin; the spring shoe plate is provided with a cross-shaped ridge portion in its front surface, which ridge portion is for a click, wherein the ridge portion is engaged with and disengaged from a T-shaped groove portion in the rear surface of the base-end portion of the control handle in accordance with one of the changeable positions of the control handle. Consequently, in the conventional door locking handle assembly having the above construction, the control handle may change its position with a click. The above door locking handle assembly is a conventional handle holding mechanism for holding the control handle in each of its changeable positions.
However, the conventional handle holding mechanism described above suffers from the following problem: namely, in the conventional mechanism, both the compression coil spring and the spring shoe plate are essential components, and therefore can't be omitted therefrom. Further, in the conventional mechanism, it is necessary to provide a large hollow portion in the cylindrical portion of the base-end portion of the stationary casing for receiving therein both the spring shoe plate and the compression coil spring, because the spring shoe plate and the compression coil spring are relatively large in thickness and in height, respectively, which makes it impossible to downsize the conventional mechanism.